[MCL-12570] Versions which inherit and re-define a library cause corrupted downloads

Potential fixes

Download the file that's said in the "URL" and place it in the folder identified by "Path"
Run the vanilla version of the game for that version, then run the modded version.

If you need additional help, please contact 💬 Community Support.

Attempting to use the following json as a version (provided by Minecraft Forge) results in several files being corrupted on their download which results in their hashes being invalid.

If a library is defined as required in the root version and a version json inherits from it and re-declares the library, the file downloads improperly and fails to launch.

If an item is declared as a library in both 1.12.2 and a child, then it seems this behavior occurs. This also has occurred with 1.7.10 Forge files.

Linked issues

is duplicated by 13

MCL-12584 JOPT NOT INSTALLING! Resolved

MCL-12684 Minecraft not launching Resolved

MCL-12691 Historical versions and old offical release versions not installing Resolved

MCL-12703 Launching The Game Failed Resolved

MCL-12730 Twitch/Minecraft Jna4.0 0 error Resolved

8 more links

relates to 1

MCL-12493 Launcher shows a warning when first trying to download a new version of the asset index Resolved

Attachments

1.11.2-forge1.11.2-13.20.0.2228.json

1.12.2-forge1.12.2-14.23.5.2847.json

Specify Java binary used in Vanilla Launcher.jpg

Comments 19

migrated 2019-11-15T03:30:05Z

From what I've seen it appears that during the download for a library defined in both parent and child a second copy of the library gets concatenated with the first one

migrated 2019-11-19T00:51:10Z

This issue can be worked around by installing the most recent version of 64 bit java, and then instructing Minecraft to use that one instead.

migrated 2019-11-19T04:47:07Z

That doesn't appear to be the case for me, John.
On my end it appears to be an issue with 1.12.2 and older, perhaps a collision between older(i.e. previously-built Forge version jsons) and current(updated by launcher) version formats?

migrated 2019-11-20T23:52:22Z

@John Possen could you please tell me how to do that? I've been having this issue and it's very annoying.

migrated 2019-11-23T19:33:57Z

How do you instruct minecraft to use the java instead?

9 more comments

migrated 2019-11-25T06:33:18Z

@Victor Li

@Gabrielle

Assuming you already have java installed locally. (just normal minecraft launching doesnt mean you do if your not sure) If not sure, open up a Command Prompt window and type

`java -version`

If you get a unknown command you dont have it most likely, Just go download it. if you do, well.....I made a nice image that makes it pretty simple and self explanatory

Link if your not able to see it here---> `https://i.imgur.com/BtRORRR.jpg`

[media]

!Specify Java binary used in Vanilla Launcher.jpg!

migrated 2019-11-25T09:55:47Z

I've found a solution so you don't have to wait. http://www.mediafire.com/folder/ba9kblhsrnx3y/jopt-simple Download this (Don't worry it's safe it's the original files) and go to .minecraft or twitch or anything libraries net sf and put it instead of the old jopt simple folder this is for 1.7.10 1.14.4 and 1.12.2

[MOD] Greymagic27 2019-11-25T12:37:59Z

I've been doing that for a while now, but it only seems to work 50% of the time

migrated 2019-12-02T04:37:44Z

@ROMVoid I changed the Java Executable to the newest version of Java which I downloaded a couple days ago, and it still comes up with an error, I used the javaw.exe. Did I miss something, or do I need to reinstall Java and try again?

migrated 2019-12-07T04:28:52Z

The error message I get when it fails has a link in it to the download location, straight from Minecraft.net, so I just downloaded from there (after coming here and finding out that I just needed to re-download, thanks guys!) instead of going to any other link.

Thanks for helping out, but I'd always rather get the download directly from the official source. Color me paranoid. 😉

Also, I think Colby is on to something. The file I deleted was 2.2 MB and the one I downloaded is 1.1 MB, so that much at least seems to indicate it is two in one. (I didn't think to look closer before I deleted it.)

migrated 2019-12-08T14:13:34Z

It seems like files are getting double sized for some reason. In my case - jopt-simple-4.5 ..\Twitch\Minecraft\Install\libraries\net\sf\jopt-simple\jopt-simple\4.5\jopt-simple-4.5.jar after trying to launch modpack - 120KB and the file downloaded from https://libraries.minecraft.net/net/sf/jopt-simple/jopt-simple/4.5/jopt-simple-4.5.jar directly is 60KB. Yesterday got near the same issue with another modpack, have to download jna-4.4.0 file manually from libraries host to run the pack.

The workaround: Download file using link from error description and put it manually to the folder from the error description overwriting existing one.

LeeSpork 2019-12-11T03:43:40Z

I'm getting the issue that I cannot launch old versions of the game such as Alpha and Infdev versions, as someone else also reported at https://bugs.mojang.com/browse/MCL-12691

Failed to download file, the file contents differ from what was expected.
Name: jinput-platform-2.0.5-natives-windows.jar
URL: https://libraries.minecraft.net/net/java/jinput/jinput-platform/2.0.5/jinput-platform-2.0.5-natives-windows.jar
Filename on disk: jinput-platform-2.0.5-natives-windows.jar
Path: C:\Users\LBLog\AppData\Roaming\.minecraft\libraries\net\java\jinput\jinput-platform\2.0.5\jinput-platform-2.0.5-natives-windows.jar
Exists: File

migrated 2019-12-12T09:56:49Z

I believe I may be running into a similar, but alternate version of this problem. Like many others, I am trying to run a modpack from Twitch but I experience a failure to launch and am given this error.

Failed to download file, the file contents differ from what was expected.
Name: jna-4.4.0.jar
URL: https://libraries.minecraft.net/net/java/dev/jna/jna/4.4.0/jna-4.4.0.jar
Filename on disk: jna-4.4.0.jar
Path: C:\Users\USER\Twitch\Minecraft\Install\libraries\net\java\dev\jna\jna\4.4.0\jna-4.4.0.jar
Exists: File

My problem is, every post from others about this error says that it can easily be fixed by manually downloading jna-4.4.0.jar and replacing the file. The thing is, I've tried this. A lot of times, to rule out the fact that I could be crazy or delirious. Over and over I've manually downloaded jna-4.4.0.jar, deleted the "wrong" jar, replaced it with the manually downloaded one, and I am still greeted with the same error time and time again.

I'm just not sure why I have the same error as so many other people and yet the fix that works for them does not work for me.

I've also attempted reinstallation of Minecraft Launcher (including deletion of original .minecraft folder) and this has made no change.

Edit: Turns out I was crazy and delirious. I was replacing jna-4.4.0.jar in my .minecraft folder rather than in the relevant Twitch subfolder.

migrated 2019-12-12T15:24:13Z

I installed 1.8.9 and ran it, and after running it I was able to install and play both historical and early release versions of the game, so maybe try that.

I'm not sure if any other versions would work, but I've tried it twice with 1.8.9 and it worked both times.

migrated 2019-12-13T09:53:51Z

I've had the same behaviour with the following config for Forge 1.11.2:

[media]

The error message is:

{{Failed to download file, the file contents differ from what was }}
{{ expected. Name: jopt-simple-4.6.jar URL: }}
{{ https://libraries.minecraft.net/net/sf/jopt-simple/jopt-simple/4.6/jopt-simple-4.6.jar}}
{{ Filename on disk: jopt-simple-4.6.jar Path: }}
{{ C:\Users\MY_USER_NAME\AppData\Roaming\.minecraft\libraries\net\sf\jopt-simple\jopt-simple\4.6\jopt-simple-4.6.jar}}
{{ Exists: File}}

This is resolved by either:

a) downloading jopt-simple-4.6.jar from the URL supplied, and placing in the path listed; or

b) installing vanilla 1.11.2 first, launching it, and then trying forge1.11.2-13.20.0.228 again.

migrated 2019-12-19T03:16:11Z

I tried uninstalling and installing the link to the folder where it asks, however, upon doing so, it deletes, but when trying to reopen a modpack (specifically on Twitch), it just adds the old jna file back, as well as keeping the downloaded on I had previously added. Causing massive frustrating as I've been trying for days now to get it to to work. If anyone has any other work arounds please let me know.

Failed to download file, the file contents differ from what was expected.
Name: jna-4.4.0.jar
URL: https://libraries.minecraft.net/net/java/dev/jna/jna/4.4.0/jna-4.4.0.jar
Filename on disk: jna-4.4.0.jar
Path: C:\Users\USERNAMEHERE\Twitch\Minecraft\Install\libraries\net\java\dev\jna\jna\4.4.0\jna-4.4.0.jar
Exists: File

migrated 2019-12-24T09:57:23Z

I have same issue :

Failed to download file, the file contents differ from what was expected.
Name: jinput-platform-2.0.5-natives-linux.jar
??URL: https://libraries.minecraft.net/net/java/jinput/jinput-platform/2.0.5/jinput-platform-2.0.5-natives-linux.jar??
Filename on disk: jinput-platform-2.0.5-natives-linux.jar
Path: /home/bensuperpc/.minecraft/libraries/net/java/jinput/jinput-platform/2.0.5/jinput-platform-2.0.5-natives-linux.jar
Exists: File

migrated 2020-01-22T04:02:35Z

alot of times makes the game unplayable and unable to launch this should be high priority and fixed immediately.

migrated 2020-07-10T08:36:25Z

Hello everyone - I would be very much interested in reproduction steps for this bug. Preferably not via applications or third parties that are modifying the game and/or the launcher!